Field of Invention
The present invention relates to a force feedback handle device with a degree-of-freedom and a working method thereof, mainly for dental surgery simulation, virtual reality and virtual assembly, which is capable of measuring positions and providing haptic feels, belonging to tactile/haptic human-computer interaction technology.
Description of Related Arts
With the development of science and technology, especially computer technology, mankind has been able to interact with the computer by visual and auditory, and multimedia and virtual reality world has come. Tactile/haptic combination of human-computer interaction and computer technology will be introduced into the tactile world of virtual reality, so that interaction ways between human, computer and robots will become more abundant. In tactile/haptic human-computer interaction technical field, force feedback devices play an important role. European and American countries have studied force feedback devices deeply, and force feedback equipment manufacturers such as SensAble and Force Dimension have been world leaders. Chinese research on force feedback devices has made a lot of progress and results. Conventional force feedback devices are impedance or admittance force feedback devices. According to the impedance model, the impedance device calculates and obtains a desired output power of the device ends through measuring the actual position or speed of the device end. The admittance device uses a force sensor for measuring the force applied by the user at the end, and uses information about the force and a virtual environment interaction force for calculating positions of virtual objects by the kinematic law as a position output of the device. For the impedance device, because of the feature of position in and force out, the device must be able to reversely drive. In order to feel full freedom at a free space, the device needs to have a sufficient back-drivability, and therefore a mechanical system of the impedance device generally has features such as low inertia, low friction and small gear ratio. The impedance device is good at simulation of free space and small stiffness, but has instability problems during large stiffness rendering. For the admittance device, due to the feature of force in and position out, the mechanical system is generally designed to have a large stiffness, such as a reduction with a large gear ratio, and mechanical parts having a large stiffness. The admittance device is good at simulation of large stiffness environment, but also has instability problems for free space and small stiffness rendering. In order to overcome defects of the impedance and admittance force feedback devices, the present invention provides a force feedback handle device with a degree-of-freedom and a working method thereof.